Hydraulic brake cylinder



Feb. 20, 1940. .J. w. LEIGHTON 2,190,? 19

HYDRAULIC BRAKE CYLINDER Filed March 2, 1936 ll 22 INVENTOR :5 Jh 11046114120 y ATTORNEYS.

a entirely of sheet metal partssecured together to therewith; 5.

' 40 forming a part thereof. flange l5 formed on the stamping II. On the- 40 66 stantlally on the line H of Fig. 1, illustrating to the semi-cylindrical configuration of the 55 Pant es. 20, 1940, 2,190,719

UNITED STATES PATENT OFFICE 2,190,719 mzmmumc BRAKE oynmnnu. John W. Leighton, Port Huron, Mich. Application March 2, 1936, Serial No. 66,517

3 Claims. (or. 309-2) li'his invention relates to hydraulicbrake cylin detail the manner in which the improved inder constructions. More particularly, it rebrake cyl nder construction is mounted on the lates to an improved formof hydraulic brake brake housing with which it is associated and cylinder construction, composed substantially showing the location of the ports communicating provide a unitary integral construction. Fig. 5 illustrates a length of copper wire bent It is a primary object of the present invention to the form utilized for welding the sections toto provide a brake cylinder construction formed gether. i substantially entirely of sheet metal in which the With more particular reference to the specific fluid supply port and the bleed port aredisposed embodiment of the invention illustrated. in the 10 in material angles to the axis of the cylinder in drawing, it will be seen that the improved .hyorder that easy access may be had thereto. draulic brake cylinder construction comprises a Still another object of the present invention pair of mating sheet metal stampings, generally consists in the provision of a brake cylinder condesignated l0 and H, which are secured together struotion comprising a pair of substantially syinface to face. It has been found essential'in the 15 metrical preformed sheet metal stampings seprovision of hydraulic brake cylinder construccured together face to face and providing'theretions of this general type to provide a pair of between the brake cylinder and the fluid supply coaxially arranged cylinders of slightly different port communicating therewith. diameter, each of which is adapted to receive a The invention further contemplates the propiston connected to one end ofthe brake shoe 20 vision of means associated with the mating which the cylinder serves to operate. This conflanges of the sheet metal stamplngs forming struotion has been found desirable due to the the cylinder construction for securing the same fact that the direction of rotation of the wheel in predetermined-position upon a brake housing requires a greater mechanical advantage upon with which the cylinder is associated. one end of the brake shoe than upon the other 25 Yet another object of the present invention due to the wrapping effect of the brake shoe on consists in the provision of a pair of mating the brake drum with which it is associated. In grooves in the mating flanges oi the sheet metal order to obtain a brake cylinder construction parts forming the improved brake cylinder conhaving the characteristics outlined: above, the struotion, which together serve to provide a deadsheet metal members l0 and ii are each provided 30 end duct having an auxiliary pipe communicating with semi-cylindrical coaxiall'y disposed deprestherewith and with the cylinder proper, in order sions l2 and I3 of slightly different diameter, to provide novel and efiective means for bleeding such that when the blanks l0 and H are arair from the cylinder at the time fluid is introranged in face to face relation, resulting duced thereinto. structure will provide a pair of coaxially disposed 35 Many other and further objects and advantages cylinders of slightly difierent diameter. of the present invention will become apparent The blank I0 is provided in one of its side from the following specification when considered edges with an axially extending flange ll which in connection with' the accompanying drawing mates with a corresponding axially extending In the drawing: opposite side of the cylinder construction the Figure 1 is a top plan view of one form of the stamping III is provided with a relatively wide improved brake cylinder construction illustratlaterally extending flange l6 which is adapted ins the same mou e u a brake housi g to mate in face to face relation with a correstructure; sponding relatively wide flange l'l formed in the 45 Fig. 2 is an end elevational view of the imsheet metal member ll. At the time the semiproved hydraulic brake cylinder construction, cylindrical depressions l2 and 13 are formed taken substantially on the line 2-2 of Fig. l; in these stampings l0 and II, a pair of angu- Fig. 3 is ahorizontal, sectional view, taken sublarly disposed grooves l8 and I9 are formed in s antially on the line 3- tF s- 2, ill tr ting each of the flanges l6 and II. It will be clearly so the interior construction of the brake cylinder seen by reference to Figure 3 that the grooves l8 and the manner in which the fluid supply port mate to provide a duct communicating with the communicates therewith; I interior of the cylinder structure formed by the Fig. 4 is a verticahsectional view, taken substampings and it will further be apparent, due

grooves from which this duct is formed, that when the stampings are placed together in face to face relation, the resulting duct structure will besubstantially cylindrical in form.

The grooves l9 are likewise semi-cylindrical in configuration and it will be seen by reference to Figure 3 that these grooves terminate short of the cylinder structure .and consequently provide a dead-end duct, the purpose and function of which will hereinafter'become clear.

A pair of lugs are pre erably provided on each. of the flanges l6 and H and it will be seen by reference to Figure 4 that these lugs 22 provide satisfactory means for securing the brake cylinder construction to the brake housing with which it is associated. The lugs 22 are preferably provided with an internally threaded aperture adapted to receive bolts 23 which extend through the wall of the brake housing structure 2% on which the hydraulic brake cylinder is to be mounted and secure the entire hydraulic brake cylinder assembly permanently in position thereon. The brake housing structure 2!! is preferably provided with an aperture of configuration such.v

that it will permit the mating portions of the flanges l6 and-l1 to extend therethrough in order that access may be had to the open end of the ducts I8 and 19.

The duct I8 is internally threaded and is adapted to receive a fluid supply fitting 25 which serves to connect a supply conduit 26 through which fluid from the master cylinder which serves to actuate the brake may be supplied to the interior of the cylinder construction of the present invention.

It will be noted that the axes of the ducts formed by the mating grooves I8 and H) are not only substantially inclined to each other, but are substantially inclined to the axis of the cylinder. 40?

Thus the outer endsof the .ducts are inherently spaced apart rather widely and hence easy access may be had thereto. .As is conventional in structures of this general character, the king pin which serves to support the wheel generally, passes the axial central portion of the cylinder and hence it is particularly desirable that the openings of the ducts be located in spaced relation to the axial central portion of the cylinder.

The sheet metal stampings I 0 and H may be secured together by copper welding in order to provide a substantially integral unitary construction and after the welding operation has been completed, the interior of the cylinders l2 and I3 invention contemplates a particularly novel method for performing this operation. A wire 30 of copper is bent to substantially the configuration shown in Figure Sand after the sections [0 .and II have been assembled in face to face relation this U-shaped wire is inserted in the cylinder formed therebetween and due to its inherent resiliency it will spring outwardly against the walls thereof thus retaining itself seated in place. The

wire 38 may be positioned so that it will be closely adjacent the joint and the whole may then be heated in an inert atmosphere and the copper from the wire will flow into the joint securing the parts together;

A suitable hole may be drilled in the upper surface of the stamping Hi to provide a bleed port at the upper portion of the cylinder construction. Likewise a suitable aperture is provided in the flange It providing communisation with the inner end of the duct is and a sun-aisle tube or conduit 27 may be welded in position substantially as is shown in Figure 2 establishing communication between this duct is and a suitable point on the upper surface of the cylinder. The duct i9 is preferably also internally threaded and may be closed by means of a suitable plug or bolt 29.

It will be readily apparent that when fluid is introduced into the cylinders l2 and It by means of the fluid, supply line it and duct l8 with which it communicates, air may be bled from the interior of the cylinders l2 and it by means of the conduit 21 and bleed duct l9. Due to the fact that this conduit 21 communicates with the top portion of the cylinder construction, it will be seen that this conduit may be utilized for the purpose of straining off all of the air within the system during the timethe fluid is being introduced into the interior of the cylinder construction.

While but one specific embodiment of the invention has been illustrated and described, it will be clearly apparent that many other and further modifications may be made. The scope of the invention is defined in the following appended claims.

I claim as my invention:

1. A hydraulic brake cylinder construction comprising a pair of sheet metal stampings each having .a semi-cylindrical depression therein and flanges at the lateral sides of said depression, a groove in one of the flanges of each of said stamping's, said stampings being secured together face to face whereby said depressions mate to form a cylinder, and said grooves mate to form a port communicating with said cylinder, and lugs on said flanges providing means for mounting said cylinder.

2. In a hydraulic brake cylinder assembly, a pair of sheet metal stamplngs preformed to provide a cylinder therebetween, said stampings also providing therebetween a fluid supply port communicating directly with the interior of said cylinder and a dead-end bleed port and a conduit connecting said dead-end port with said cylinder.

3. A hydraulic brake cylinder construction comprising a pair of sheet metal stampings, each having a pair of co-axially arranged semi-cylindrical depressions therein and each having flanges at the lateral sides of said depressions, a groove in one of the flanges of each of said stampings, said stampings being secured together faceto-face whereby said depressions mate to form a pair of co-axially disposed cylinders and said grooves mate ,to form a port communicating with said .cylinders.

- JOHN W. LEIGHTON. 

